Whatever opinion you might have on JYJ, it cannot be denied that they fought to establish their rights, however the merit on their cases.
Because of their struggle, the "Standard Contract" was 'suggested' by the Government on 2009 .
Its chief tenets included these two very important clauses
1. The 'Standard" length of an artist to the company was seven years, 84 months. (That could be extended in case of the member's military service, medical conditions and other situations caused by the artists.)
2. The companies should not interfere with the personal conduct of the artists unless that interfered with their ability to perform (i.e. get arrested, etc).
The companies didn't like it. When JYJ broke the contract it was 13 years long, and Yoona had a LIFETIME contract with SM. Other acts were run in a similar way and it was very common for idol members to not collect anything after the contract was usually ended unilaterally by the company.
The companies didn't like that from the start, but since the government showed a 'guideline' the courts tended to use the 'Standard Contract" as the standard to judge the legality of a contract , and although there were quite a few abuses, as we have seen in Chuu's case the Standard Contract had become the legal basis for the idol members to fight the abuses of the company.
The Fifty Fifty case , however you see it, has changed the opinion the Koreans have on the companies.
With BlackPink's contract renewal status not clear even now, and with KPop acts lasting longer because of overseas activities, companies want to extend their basic contract years to something far longer than 7 years, since if an act lasted more than 7 years that means it now has a steady foreign following.
In addition they want to make sure their ability to pressure the idols are legally affirmed, to prevent cases like Chuu or Fifty Fifty.
These changes would be very favorable for the companies and very unfavorable towards the idols, but a lot of Koreans , buoyed by the Atrakt owner's blatant media play, are now supporting the companies.
The companies want to restore the "Slave Contract", where the companies would take most of the artists' income and would leave them with nothing after they are no longer marketable, and artists no longer allowed to sue their companies.
I personally think the companies will win, because of Korea's long tradition of landowner/slave mentality. Korea legally maintained slaves until 1894, something not too many people know about, and unofficially such relationship existed until 1950s.
The companies will force the "Slave Contracts", although whether the foreign members will bite them is another matter.